.a-btn_blue{
    width:140px;
    height:140px;
    -webkit-border-radius:50%;
    -moz-border-radius:50%;
    border-radius:50%;
    display:block;
    margin:20px;
    float:left;
    background:rgba(0, 151, 255, 0.6);
    position:relative;
 
}
.a-btn_blue span{
    display:table-cell;
    width:100px;
    height:100px;
    padding:20px;
    text-align:center;
    vertical-align:middle;
    font-size:16px;
    color:#fff;
    text-shadow:0px 1px 1px #000000;  
    -webkit-transition:all 0.3s linear;
    -moz-transition:all 0.3s linear;
    -o-transition:all 0.3s linear;
    transition:all 0.3s linear;
}
.a-btn_blue span:nth-child(1), 
.a-btn_blue span:nth-child(3){
    position:absolute;
    top:0px;
    left:0px;
    opacity:0;
	font-size:16px;
    line-height:24px;
	margin-top:40px;
}
.a-btn_blue span:nth-child(1){
    opacity:0.2;
}
.a-btn_blue:hover{
       background:#0082f2;
  
}
.a-btn_blue:hover span:nth-child(3){
    opacity:1;
	width:100px;
    height:100px;
    padding:20px;
    text-align:center;
    vertical-align:middle;
    font-size:16px;
    color:#fff;
    text-shadow:0px 1px 1px #000000;  
    -webkit-transition:all 0.3s linear;
    -moz-transition:all 0.3s linear;
    -o-transition:all 0.3s linear;
    transition:all 0.3s linear;
}
.a-btn_blue:hover span:nth-child(2){
    opacity: 0; 
    -webkit-transform: scale(0);
    -moz-transform: scale(0);
    transform: scale(0);
	
}
.a-btn_blue:hover span:nth-child(1){
    -webkit-animation:rotate 1s linear;
    -moz-animation:rotate 1s linear;
    animation:rotate 1s linear;
}


@keyframes rotate{
    0% { transform: scale(1) rotate(0);}
    50% { transform: scale(0.5) rotate(180deg);}
    100% { transform: scale(1) rotate(360deg);}
}
@-webkit-keyframes rotate{
    0% { -webkit-transform: scale(1) rotate(0);}
    50% { -webkit-transform: scale(0.5) rotate(180deg);}
    100% { -webkit-transform: scale(1) rotate(360deg);}
}
@-moz-keyframes rotate{
    0% { -moz-transform: scale(1) rotate(0);}
    50% { -moz-transform: scale(0.5) rotate(180deg);}
    100% { -moz-transform: scale(1) rotate(360deg);}
}
